C-reactive protein ; Friend or Foe? Ki Hoon Han MD PhD Asan Medical Center Seoul, Korea
I. Inflammation and atherogenesis Atherosclerosis is an inflammatory disease
Recruitment of Blood Monocytes by Endothelial Cell Adhesion Molecules Monocyte Rolling Sticking Vessel Lumen Transmigration E-Selectin VCAM-1 ICAM-1 MCP-1 Endothelium Intima Charo IF. Curr Opin Lipidol 1992;3:335-343.
Modified LDL Stimulates Expression of MCP-1/adhesion molecules in Endothelial Cells Monocyte Vessel Lumen LDL E- Selectin VCAM-1 ICAM-1 MCP-1 LDL Endothelium Modified LDL Intima Navab M et al. J Clin Invest 1991;88:2039-2046.
Differentiation of Monocytes into Macrophages Monocyte Vessel Lumen LDL MCP-1 LDL Modified LDL Endothelium Intima Macrophage Modified LDL Promote Differentiation of Monocytes into Macrophages Steinberg D et al. N Engl J Med 1989;320:915-924.
The process of LDL modification LDL Readily Enter the Artery Wall Where They May be Modified LDL Vessel Lumen Oxidation of Lipids and ApoB Aggregation LDL Endothelium Hydrolysis of Phosphatidylcholine to Lysophosphatidylcholine Other Chemical Modifications Modified LDL Modified LDL are Proinflammatory Intima Steinberg D et al. N Engl J Med 1989;320:915-924.
Oxidation changes components of LDL particles LDL OxLDL Ox-apoB Ox-lipid microemulsion
Modified LDL Induces Macrophages to Release Cytokines That Stimulate Adhesion Molecule Expression in Endothelial Cells Adhesion Molecules Monocyte Vessel Lumen LDL MCP-1 LDL Endothelium Cytokines Modified LDL Macrophage Intima Nathan CF. J Clin Invest 1987;79:319-326.
Macrophages Express Receptors That Take up Modified LDL Adhesion Molecules Monocyte Vessel Lumen LDL MCP-1 LDL Endothelium Modified LDL Taken up by Macrophage Foam Cell Macrophage Intima Steinberg D et al. N Engl J Med 1989;320:915-924.
Macrophages and Foam Cells Express Growth Factors and Proteinases Monocyte Vessel Lumen LDL Adhesion Molecules Cytokines MCP-1 Modified LDL LDL Endothelium Intima Growth Factors Metalloproteinases Macrophage Cytokines Foam Cell Cell Proliferation Matrix Degradation Ross R. N Engl J Med 1999;340:115-126.
Atherosclerosis is an Inflammatory Disease Monocyte Vessel Lumen Cytokines Endothelium Growth Factors Metalloproteinases Cell Proliferation Matrix Degradation Foam Cell Macrophage Intima Ross R. N Engl J Med 1999;340:115-126.
Atheroma Growth (-) Plaque rupture Cell Apoptosis Cyto/chemokines Growth Factors Cell Migration Cell Proliferation Atheroma Growth (+)
II. C-reactive protein and inflammation
C - reactive protein Known for 70 years (discovered in 1930) CRP Binds with phosphocholine (calcium dependent) in bacterial and fungal polysaccharides
C - reactive protein Known for 70 years Binds with phosphocholine Ca++ PCh CRP Recognized by C1q - complement activation Phagocytosed thru FcrI and IIR
C - reactive protein Known for 70 years Binds with phosphocholine Recognized by C1q - complement activation and Phagocytosed thru FcrI and IIR Chromosome 1 btw 1q21 and 1q23 2263 nt one intron 1.2 kb 3 ut CRP PCh C1q C activation FcrI and IIR
C - reactive protein Known for 70 years Binds with phosphocholine Recognized by C1q - complement activation and Phagocytosed thru FcrI and IIR Chromosome 1 btw 1q21 and 1q23 2263 nt one intron 1.2 kb 3 ut CRP PCh C1q C activation FcrI and IIR
Inflammation IL 1beta (+) IL - 6 C/EBP (CCAAT enhancer binding protein) ATG 5 3-53
C - reactive protein Known for 70 years Binds with phosphocholine Recognized by C1q - complement activation and Phagocytosed thru FcrI and IIR Chromosome 1 btw 1q21 and 1q23 2263 nt one intron 1.2 kb 3 ut CRP PCh C1q C activation FcrI and IIR
Endoplasmic reticulum
C - reactive protein Known for 70 years Binds with phosphocholine Recognized by C1q - complement activation and Phagocytosed thru FcrI and IIR Chromosome 1 btw 1q21 and 1q23 2263 nt one intron 1.2 kb 3 ut CRP PCh C1q C activation FcrI and IIR
Bacteria Fungi Dead Cells Dying Cells CRP - ligand complex Binding to C1q Binding to FcrRI and RII on macrophages and neutrophils Activation of classical complement (C1-C9) Opsonization and phagocytosis
III. C-reactive protein is a good marker for the Atherosclerotic disease
ATHEROSCLEROSIS Infection Rheumatoid arthritis CRP Crohn s disease SLE polymyositis acute leukemia ulcerative colitis
C-reactive protein FROM PAUPER TO PRINCE REVIVAL!!!
Prognostic Influence of Increased CRP in unstable CAD Toss et al, Circulation,1997,96:4204 28 Toss et.al. Circulation 1997,96:4204
Prognostic Value of Baseline CRP According to Initial Clinical Presentation Mulhlestein et al, Circulation, 2000, 102:1917 Mulhlestein et.al. Circulation 2000,102:1917 29
Pre-procedure serum CRP level can predict Early Complications & Late Restenosis after PTCA Clinical Restenosis Major CV events Open bar ; CRP 0.3 mg/dl Black bar ; CRP > 0.3 mg/dl Buffon et. al. JACC 1999,34:1512
Plasma Levels of CRP after Stent Implantation Gottsaunder-Wolf et. al. Eur Heart J 2000,21:1152
1. CRP elevated after Stenting. 2. CRP, 72 hours after stenting can predict CV events. Gasparone et. al. Am J Cardiol 1998,82:515
Ridker et al NEJM 2002;347:1557
Distribution of hscrp in Korean population Chang JW et. al. Am J Kid Dis 39,2002:1213-1217 healthy volunteers n=1399 median = 0.64 mg/l (<0.006 to 0.567 mg/l) 25th = 0.34 75th = 1.23 95th = 4.01
High-Sensitivity CRP and TC/HDL-C - risk assessment in primary prevention of CVD Men Women TC: HDLC ratio for men <3.5, 3.5 to 4.3, 4.4 to 5.0, 5.1 to 6.1, and >6.1 for women <3.1, 3.1 to 3.6, 3.7 to 4.3, 4.4 to 5.2, and >5.2 (Harvey Kaufman, MD, personal communication, 2001). Ridker Circulation 2001,103:1813 Ridker, Circulation, 2001, 103:1813 37
Risk of Cardiovascular Events among Healthy Postmenopausal Women CRP SAA sicam-1 IL-6 Ridker et.al. Ridker et al, NEJM, 2000,342:863 38 NEJM 2000,342:863
High-Sensitivity CRP - risk assessment in primary prevention of CVD - Ridker Circulation 2001,103:1813 Factors related to CRP 인종 B >W Gender female > male Age + Hypertension + Insulin sensitivity + Smoking ++ Glucose tolerance ++ Obesity +++ Coagulation activity ++ IMT of int. carotid a. + Ridker, Circulation, 2001, 103:1813 39
Direct comparison of magnitude of relative risk of future cardiovascular events Ridker, Circulation, 2001, Ridker 103:1813 Circulation 2001,103:1813 40
III. C-reactive protein may affect the process of Atherosclerosis
CRP Inflammatory Marker Inflammatory Mediator
The origin of CRP in the plaque? De novo synthesis by VSMCs and macrophages ; Circulation. 2003 108(16):1930-2 Exp Biol Med. 2005 230(10):762-70 Mainly from blood circulation Am J Pathol. 2005 Oct;167(4):1139-48 Maybe from both Am J Pathol. 2001 Mar;158(3):1039-51
CRP antisense probe Lane 1, normal artery; lane 2, plaque tissue; lane 3, lane 4, heart; lane 5, kidney; lane 6, spleen. Human autopsy sample Am J Path 2001;158:1039
C - reactive protein ; proinflammatory? - Complement activation - produced by macrophages and SMCs in plaques - colocalized with membrane attack complex - produce IL-1 beta, IL-6 and TNF-alpha by monocytes - produce ICAM-1 and VCAM-1 and MCP-1 by endothelial cells Am J Med Sci 2000;319:77 Am J Path 2001;158:1039 Circulation 2000;102:2165 Circulation 2001;103:2531
Accumulation of monocytes/macrophages Produce MCP1/adh. molecules by endothelial cells oxldl uptake by macrophages complement Foam cell formation CRP Produce proinfl. Cytokines by macrophages Activate ma. And T cells
Can we reduce blood CRP levels? YES 1. Statins (Atherosclerosis 165:361, 157:411) 2. PPAR ligands ; alpha- and gamma (Circulation 106:679) 3. Aspirin (Circulation 100:793) 4. Antibiotics ; azithromycin (Circulation 105:1298, 106:1071) roxithromycin (Eur Hrt J 120:121)
To prevent cardiovascular events 1. Life style modification - lipid lowering can stabilize atheroma 2. Statins 3. PPAR-gamma ligands 4. Aspirin 5. Antibiotics? Reduce inflammation
IV. C-reactive protein and Hypertension
CRP elevates Blood Pressure?
CRP elevates Blood Pressure through AT2R downregulation Circulation 2007;115:1020-1028
CRP and Coronary Disease Relative risk 3 2 1 0 3mg/L difference 1 2 3 4 5 Quintile of hs-crp 1 2 3 4 5 Relative Risk (95% CI) 8 7 6 5 4 3 2 1 Systolic Blood Pressure And C-Reactive Protein CRP <1mg/L CRP 1 to <3mg/L CRP 3mg/L 0 <110 mmhg 110-119 mmhg120-129 mmhg Systolic Blood Pressure Relative risk of future coronary events according to quintiles of CRP. Ridker P. Circulation 2001; 103 (13): 1813-8. Association between increasing CRP concentration and systolic blood pressure. Sesso et al. JAMA 2003; 290 (22):2945-51.
V. C-reactive protein Controversies
CRP is nothing more than a marker? Reported CRP effects are not really from CRP May be due to sodium azide, endotoxin, or/and immunoglobulin.
CRP enhances MCP-1 mediated chemotaxis of monocytes Number of Cells per X400 Field 30 25 20 15 10 5 MCP-1 Buffer only * ** * 0 Control CRP CRP+FC FC Circulation 2004 Jun 1;109(21):2566-71
CRP upregulates monocyte chemotaxis receptor for MCP-1, CCR2 CCR2 protein (% of control) 200 150 100 50 CRP CRP + Polymyxin B ** * ** ** * * 0 0 1 5 10 CRP (mg/ml/24h) Circulation 2004 Jun 1;109(21):2566-71
CRP enhances CCR2 expression by monocytes and MCP-1-induced chemotaxis CRP CD64 CCR2 upregulation PLD1 activation MONOCYTES More MCP-1- induced chemotaxis Circulation 2004 Jun 1;109(21):2566-71
CRP induces apoptosis of VSMCs and cytokine release from VSMCs CRP FcγRIIa GTP-Rac Nox4 p22phox p47phox GTP-Rac p47phox AP-1 NFkB ROS MCP-1 IL-6 ET-1 Apoptosis Cardiovasc Res. 2007 Aug 1;75(3):555-65
Evidences that CRP is atherogenic Devaraj S, Singh U, Jialal I. Clin Chem. 2009 Feb;55(2):229-38
Is CRP always bad?
CRP and foam cell formation (-) Foam Cells (-) (+)?? Witztum et.al.
C-reactive protein under oxidative condition ; anti-atherogenic? CRP inhibits the binding of OxLDL to scavenger receptor and subsequent uptake of OxLDL CRP inhibits the lysopc-induced NFkB activation
How can CRP-LPC less activate VSMCs? LPC FcγRIIa CRP GTP-Rac Nox4 p22phox p47phox GTP-Rac ROS p47phox CRP AP-1 NFkB MCP-1 IL-6 ET-1 Apoptosis LPC CRP Han et.al. Unpublished
CRP-induced apoptosis becomes less potent in the presence of LPC MOCK Untreated CRP LPC CRP + LPC tcrp FITC- Annexin V PI TUNEL Han et.al. Unpublished
CRP has another face CRP prevented the formation of membrane attack complex induced by enzymatically modified LDL (E-LDL). Bhakdi,S, M Torzewski, K Paprotka, S Schmitt, H Barsoom, P Suriyaphol, S Han, K J Lackner, M Husmann, 2004, Possible protective role for C-reactive protein in atherogenesis: Circulation, v. 109, p. 1870-1876. CRP-induced complement activation did not occur when CRP bound to apoptotic cells, while production of tumor growth factor alpha, an anti-inflammatory cytokine, was sustained. Gershov,D, S Kim, N Brot, K B Elkon, 2000, C-reactive protein binds to apoptotic cells, protects the cells from assembly of the terminal complement components, and sustains an antiinflammatory innate immune response: implication for symmetric autoimmunity: J Exp Med, v. 192, p. 1353-1364.
CRP tends to retard atherogenesis and inhibit foam cell formation in CRP/LDLR double KO mice Cholesterol Triglyceride LDLR(-/-) mice WT hcrptg Han et.al. Unpublished